Immersed ultrafiltration membrane automatic exhaust device

Abstract

The invention relates to an immersed ultrafiltration membrane automatic exhaust device which is characterized in that an ultrafiltration membrane is arranged in a membrane pool, the upper end of the ultrafiltration membrane is connected with an upper water collecting pipe, and one end, far away from the ultrafiltration membrane, of the upper water collecting pipe extends out of the membrane pool; an inlet of the gas-water separator is connected with the end part of the upper water collecting pipe, low-liquid-level switches and high-liquid-level switches are arranged in the gas-water separation chamber, and the low-liquid-level switches are arranged below the high-liquid-level switches at intervals; one end of the exhaust pipeline is connected with an exhaust port of the gas-water separator; and the electromagnetic valve and the vacuum pump are sequentially mounted in the exhaust pipeline. According to the scheme, starting and stopping of the vacuum pump are accurately controlled by means of high-position stopping and low-position starting of the vacuum pump, the risk that the vacuum pump is damaged due to the fact that water in membrane filaments is sucked into the vacuum pump by the vacuum pump is prevented, electric power is saved, gas in the membrane filaments of the ultrafiltration membrane is automatically and timely exhausted, and it is guaranteed that the effective filtering area of the membrane is sufficient; the influence on the water yield of the ultrafiltration device is avoided, and the economical efficiency and the safety of equipment operation are greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of water purification equipment, in particular to an automatic exhaust device for an immersed ultrafiltration membrane. Background Art

[0002] During the water production process of the immersed ultrafiltration membrane that relies on the pressure of the pool itself or the self-priming pump to produce water, due to the precipitation of gas dissolved in water or the switching action of the valve during the backwashing process, part of the gas will enter the membrane fibers of the ultrafiltration membrane along the pipeline along the water outlet. During normal water production, the membrane fibers on the upper part of the membrane curtain are generally in a negative pressure state, and the gas that overflows and accumulates in the membrane fibers is not easy to be discharged by itself, thereby reducing the effective filtration area of ​​the ultrafiltration membrane, causing the water production of the ultrafiltration device to decrease, and the reduction in membrane flux caused by bubbles cannot be restored by chemical cleaning methods. Summary of the invention

[0003] The object of the present invention is to provide an automatic exhaust device for submerged ultrafiltration membrane, which is used to solve the problem that gas accumulation reduces the effective filtration area of ​​the ultrafiltration membrane, resulting in a decrease in the water production of the ultrafiltration device.

[0004] According to one aspect of the present invention, there is provided an automatic exhaust device for an immersed ultrafiltration membrane, comprising: A membrane pool, wherein an ultrafiltration membrane is immersed below the liquid surface inside the membrane pool, an upper water collecting pipe is connected to the upper end of the ultrafiltration membrane, and one end of the upper water collecting pipe away from the ultrafiltration membrane extends to the outside of the membrane pool; An air-water separator, wherein the inlet of the air-water separator is connected to the end of the upper water collecting pipe, and an air-water separation chamber is formed inside the air-water separator. A low liquid level switch and a high liquid level switch are arranged in the air-water separation chamber, and the low liquid level switch is arranged below the high liquid level switch at intervals; an exhaust pipeline, one end of which is connected to the exhaust outlet of the gas-water separator; and A solenoid valve and a vacuum pump are installed in the exhaust pipeline in sequence.

[0005] In one of the embodiments, the submerged ultrafiltration membrane automatic exhaust device further includes a pressure sensor, and the pressure sensor is arranged on the outside of the top position of the gas-water separator.

[0006] In one embodiment, the installation height of the gas-water separator is located near the liquid level in the membrane pool.

[0007] In one embodiment, the solenoid valve is a normally closed solenoid valve.

[0008] In one embodiment, a plurality of the ultrafiltration membranes are provided, and the plurality of ultrafiltration membranes are arranged side by side and spaced apart and connected in parallel.

[0009] In one embodiment, a bracket is installed on the side wall of the gas-water separation chamber, and the bracket has a first bearing groove and a second bearing groove. The high liquid level switch is installed in the first bearing groove, and the low liquid level switch is installed in the second bearing groove.

[0010] In one embodiment, the submerged ultrafiltration membrane automatic exhaust device also includes a lower water production pipe, a self-priming pump and a clean water tank, one end of the lower water production pipe is connected to the lower end of the ultrafiltration membrane, the other end of the lower water production pipe is connected to the clean water tank, and the self-priming pump is installed in the lower water production pipe.

[0011] In one embodiment, the submerged ultrafiltration membrane automatic exhaust device also includes a backwash pipe and a backwash pump, one end of the backwash pipe is connected to the lower water production pipe, the other end of the backwash pipe is connected to the clean water tank, and the backwash pump is installed in the backwash pipe.

[0012] In one of the embodiments, the submerged ultrafiltration membrane automatic exhaust device further includes a first control valve, and the first control valve is disposed in the lower water production pipe.

[0013] In one of the embodiments, the submerged ultrafiltration membrane automatic exhaust device further includes a second control valve, and the second control valve is arranged in the backwash pipe.

[0014] Implementing the embodiments of the present invention will have the following beneficial effects: When the submerged ultrafiltration membrane automatic exhaust device of the present scheme is working normally to produce water, the solenoid valve is opened and the vacuum pump is turned on at the same time, so that a vacuum environment is formed in the gas-water separation chamber, and a negative pressure suction effect is generated on the membrane filaments of the ultrafiltration membrane, so that the tiny bubbles overflowing from the membrane filaments float up and collide with each other to merge into large bubbles, and finally flow into the gas-water separation chamber through the upper water collecting pipe, so that the gas sucked into the gas-water separation chamber is discharged from the gas-water separation chamber from the exhaust pipe; further, under the action of the suction force, the water in the membrane filaments also enters the gas-water separation chamber, and the liquid level in the gas-water separator gradually rises. When the liquid level reaches the high liquid level switch, the high liquid level switch sends a signal to close the solenoid valve and stop the vacuum pump at the same time. As the device continues to run, some bubbles overflowing from the membrane filaments of the ultrafiltration membrane enter the gas-water separation chamber, increasing the air pressure in the gas-water separator and causing the liquid level to drop. When the liquid level contacts the low liquid level switch, the low liquid level switch sends a signal to control the solenoid valve to open again, and the vacuum pump is turned on again to start sucking the tiny bubbles in the membrane filaments again, and the above process is repeated over and over again. In other words, this solution uses the high-position stop and low-position start of the vacuum pump to accurately control the start and stop of the vacuum pump, prevents the vacuum pump from sucking water in the membrane filaments into the vacuum pump and causing the risk of damage to the vacuum pump, saves electricity, and automatically and promptly discharges the gas in the membrane filaments of the ultrafiltration membrane, ensuring that the effective filtration area of ​​the membrane is sufficient, avoiding affecting the water production of the ultrafiltration device, and greatly increasing the economy and safety of equipment operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 The figure is a schematic structural diagram of an automatic exhaust device for an immersed ultrafiltration membrane according to an embodiment.

[0017] in: 100. Automatic exhaust device for submerged ultrafiltration membrane; 10. Membrane tank; 20. Ultrafiltration membrane; 30. Upper water collecting pipe; 40. Gas-water separator; 50. High liquid level switch; 60. Low liquid level switch; 70. Exhaust pipeline; 80. Solenoid valve; 90. Vacuum pump; 90a. Pressure sensor; 90b. Lower water production pipe; 90c. Self-priming pump; 90d. Clean water tank; 90e. Backwash pipe; 90f. Backwash pump; 90g. First control valve; 90h. Second control valve. DETAILED DESCRIPTION

[0018] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0019] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0021] Please refer to Figure 1 , is an automatic exhaust device for an immersed ultrafiltration membrane 20 described in an embodiment, which includes a membrane pool 10, an ultrafiltration membrane 20 is immersed below the liquid level inside the membrane pool 10, the upper end of the ultrafiltration membrane 20 is connected to an upper water collecting pipe 30, and one end of the upper water collecting pipe 30 away from the ultrafiltration membrane 20 extends to the outside of the membrane pool 10; an air-water separator 40, the inlet of the air-water separator 40 is connected to the end of the upper water collecting pipe 30, and an air-water separation chamber is formed inside the air-water separator 40, and a low liquid level switch 60 and a high liquid level switch 50 are arranged in the air-water separation chamber, and the low liquid level switch 60 is arranged below the high liquid level switch 50 at intervals; an exhaust pipeline 70, one end of the exhaust pipeline 70 is connected to the exhaust port of the air-water separator 40; and a solenoid valve 80 and a vacuum pump 90, which are installed in the exhaust pipeline 70 in sequence.

[0022] Implementing the embodiments of the present invention will have the following beneficial effects: When the automatic exhaust device of the submerged ultrafiltration membrane 20 of the present scheme is working normally to produce water, the solenoid valve 80 is opened, and the vacuum pump 90 is turned on at the same time, so that a vacuum environment is formed in the gas-water separation chamber, and a negative pressure suction effect is generated on the membrane filaments of the ultrafiltration membrane 20, so that the tiny bubbles overflowing from the membrane filaments float up and collide with each other and merge into large bubbles, and finally flow into the gas-water separation chamber through the upper water collecting pipe 30, so that the gas sucked into the gas-water separation chamber is discharged from the gas-water separation chamber through the exhaust pipe 70; further, under the action of the suction force, the water in the membrane filaments also enters the gas-water separation chamber, and the gas in the gas-water separator 40 The liquid level gradually rises. When the liquid level reaches the high liquid level switch 50, the high liquid level switch 50 sends a signal to close the electromagnetic valve 80 and stop the vacuum pump 90. As the device continues to operate, some bubbles overflowing from the membrane filaments of the ultrafiltration membrane 20 enter the gas-water separation chamber, increasing the air pressure in the gas-water separator 40, causing the liquid level to drop. When the liquid level contacts the low liquid level switch 60, the low liquid level switch 60 sends a signal to control the electromagnetic valve 80 to open again, and the vacuum pump 90 is turned on again to start sucking the tiny bubbles in the membrane filaments again, and the above process is repeated over and over again. In other words, this scheme uses the high-position stop and low-position start of the vacuum pump 90 to accurately control the start and stop of the vacuum pump 90, prevent the vacuum pump 90 from sucking the water in the membrane filaments into the vacuum pump to damage the vacuum pump 90, save electricity, automatically and timely discharge the gas in the membrane filaments of the ultrafiltration membrane 20, ensure the effective filtration area of ​​the membrane is sufficient, avoid affecting the water production of the ultrafiltration device, and greatly increase the economy and safety of the equipment operation.

[0023] See also Figure 1 In one embodiment, the automatic exhaust device of the submerged ultrafiltration membrane 20 further includes a pressure sensor 90a, which is arranged outside the top position of the gas-water separator 40. In some extreme cases, such as serious fouling of the membrane wire, in order to ensure the water production, the operating frequency of the self-priming pump 90c is increased, resulting in a larger vacuum degree in the upper part of the gas-water separator 40, which may cause the membrane wire to be deflated. At this time, the pressure sensor 90a installed above the gas-water separator 40 transmits the vacuum degree signal to the control system. Once the vacuum degree is greater than the preset vacuum degree, the system will alarm and shut down, and the host computer will prompt that the membrane curtain needs to be cleaned or replaced, ensuring the safe operation of the equipment.

[0024] In one embodiment, the installation height of the gas-water separator 40 is located near the liquid level in the membrane pool 10. That is, the liquid level in the gas-water separation chamber is close to the liquid level in the membrane pool 10, thereby reducing the liquid level difference and pressure difference between the two, so that when a vacuum environment is formed in the gas-water separation chamber, the bubbles and water in the membrane filaments of the ultrafiltration membrane 20 can be effectively sucked to achieve effective gas-water separation.

[0025] In the present application, the solenoid valve 80 is a normally closed solenoid valve, so as to avoid the pressure in the gas-water separation chamber being unstable due to the opening of the solenoid valve 80 when the device is working normally to produce water, thereby affecting the production stability.

[0026] In one embodiment, a plurality of ultrafiltration membranes 20 are provided, and the plurality of ultrafiltration membranes 20 are arranged side by side and spaced apart and connected in parallel. In this way, the plurality of ultrafiltration membranes 20 work simultaneously, which can further increase the water production per unit time.

[0027] In order to facilitate the installation and fixation of the high liquid level switch 50 and the low liquid level switch 60, and at the same time to make a preset and stable height distance between the high liquid level switch 50 and the low liquid level switch 60, in one embodiment, a bracket is installed on the side wall of the gas-water separation chamber, and the bracket has a first bearing groove and a second bearing groove, the high liquid level switch 50 is installed in the first bearing groove, and the low liquid level switch 60 is installed in the second bearing groove.

[0028] For example, the first bearing groove and the second bearing groove are both through grooves. After the high liquid level switch 50 and the low liquid level switch 60 are inserted into the through grooves, the sensing parts of the two liquid level switches can be exposed from the through grooves, so that when the liquid level in the gas-water separation chamber rises or falls, it can be detected in time, and then the working instructions can be sent to the solenoid valve 80 and the vacuum pump 90 in time to better complete the gas-water separation operation.

[0029] See also Figure 1 In one embodiment, the automatic exhaust device of the submerged ultrafiltration membrane 20 also includes a lower water production pipe 90b, a self-priming pump 90c and a clean water tank 90d, one end of the lower water production pipe 90b is connected to the lower end of the ultrafiltration membrane 20, the other end of the lower water production pipe 90b is connected to the clean water tank 90d, and the self-priming pump 90c is installed in the lower water production pipe 90b.

[0030] In addition, the automatic exhaust device of the submerged ultrafiltration membrane 20 also includes a backwash pipe 90e and a backwash pump 90f, one end of the backwash pipe 90e is connected to the lower water production pipe 90b, the other end of the backwash pipe 90e is connected to the clean water tank 90d, and the backwash pump 90f is installed in the backwash pipe 90e. The backwash pump 90f provides the power required for the flow of clean water, so that the clean water in the clean water tank 90d is pumped into the ultrafiltration membrane 20 at a certain water pressure, so as to realize the online flushing of the ultrafiltration membrane 20, restore the clean state of the ultrafiltration membrane 20, and ensure the filtering capacity of the ultrafiltration membrane 20.

[0031] See also Figure 1In another embodiment, the automatic exhaust device of the submerged ultrafiltration membrane 20 further includes a first control valve 90g, which is disposed in the lower water production pipe 90b. Similarly, the automatic exhaust device of the submerged ultrafiltration membrane 20 further includes a second control valve 90h, which is disposed in the backwash pipe 90e. The first control valve 90g and the second control valve 90h can respectively control the on-off state and opening degree of the lower water production pipe 90b and the backwash pipe 90e to regulate the water flow to meet the requirements of different working conditions.

[0032] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An automatic exhaust device for submerged ultrafiltration membrane, characterized in that: include: A membrane pool, wherein an ultrafiltration membrane is immersed below the liquid surface inside the membrane pool, an upper water collecting pipe is connected to the upper end of the ultrafiltration membrane, and one end of the upper water collecting pipe away from the ultrafiltration membrane extends to the outside of the membrane pool; An air-water separator, wherein the inlet of the air-water separator is connected to the end of the upper water collecting pipe, and an air-water separation chamber is formed inside the air-water separator. A low liquid level switch and a high liquid level switch are arranged in the air-water separation chamber, and the low liquid level switch is arranged below the high liquid level switch at intervals; an exhaust pipeline, one end of which is connected to the exhaust outlet of the gas-water separator; and A solenoid valve and a vacuum pump are installed in the exhaust pipeline in sequence.

2. The automatic exhaust device for submerged ultrafiltration membrane according to claim 1, characterized in that: The submerged ultrafiltration membrane automatic exhaust device also includes a pressure sensor, which is arranged on the outside of the top position of the gas-water separator.

3. The automatic exhaust device for submerged ultrafiltration membrane according to claim 1, characterized in that: The installation height of the gas-water separator is located near the liquid level in the membrane pool.

4. The automatic exhaust device for submerged ultrafiltration membrane according to claim 1, characterized in that: The solenoid valve is a normally closed solenoid valve.

5. The automatic exhaust device for submerged ultrafiltration membrane according to claim 1, characterized in that: A plurality of the ultrafiltration membranes are provided, and the plurality of the ultrafiltration membranes are arranged side by side and spaced apart and connected in parallel.

6. The automatic exhaust device for submerged ultrafiltration membrane according to claim 1, characterized in that: A bracket is installed on the side wall of the gas-water separation chamber. The bracket has a first bearing groove and a second bearing groove. The high liquid level switch is installed in the first bearing groove, and the low liquid level switch is installed in the second bearing groove.

7. The automatic exhaust device for submerged ultrafiltration membrane according to claim 1, characterized in that: The submerged ultrafiltration membrane automatic exhaust device also includes a lower water production pipe, a self-priming pump and a clear water tank. One end of the lower water production pipe is connected to the lower end of the ultrafiltration membrane, and the other end of the lower water production pipe is connected to the clear water tank. The self-priming pump is installed in the lower water production pipe.

8. The automatic exhaust device for submerged ultrafiltration membrane according to claim 7, characterized in that: The submerged ultrafiltration membrane automatic exhaust device also includes a backwash pipe and a backwash pump, one end of the backwash pipe is connected to the lower water production pipe, the other end of the backwash pipe is connected to the clean water tank, and the backwash pump is installed in the backwash pipe.

9. The automatic exhaust device for submerged ultrafiltration membrane according to claim 8, characterized in that: The submerged ultrafiltration membrane automatic exhaust device also includes a first control valve, which is arranged in the lower water production pipe.

10. The automatic exhaust device for submerged ultrafiltration membrane according to claim 9, characterized in that: The submerged ultrafiltration membrane automatic exhaust device also includes a second control valve, which is arranged in the backwash pipe.

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